The Number 23

Hey guys I had an old laptop running XP Pro. A couple of weeks ago, every time I would connect to the internet via DSL or wireless, the hard drive light would come on - as if it were writing something to the hard drive. It would cause IE to run slower than dial-up. I looked in task manager and although the CPU usage was high, there didn't seem to be a process listed that was using it. I used LavaSoft Adaware to scan on a regular basis as well as Norton 2005. I eventually gave up and bought a new laptop (Vista Home), which now has the same problem. It is obviously related to something that I copied over to the new computer from the old computer. But the things is, Norton Internet security isn't picking up a virus. I used it to scan everything before copying it on to the new computer. Has anyone heard of such a thing or had the same problem? I'd much rather be able to find and remove the problem rather than restore. Thanks!